"I have lost confidence in Kathleen Wynne and her ability to deliver," Horwath said Friday. "I cannot in good conscience support a government that people don’t trust anymore."

Horwath's announcement comes a day after she stayed silent as the Liberals released their budget on Thursday.

On Friday, she listed a number of scandals she says have caused her to lose confidence in the Wynne government. She also pointed to a number of undelivered Liberal promises.

Wynne had given Horwath a May 8 deadline to indicate whether she would support the budget. With Progressive Conservative Leader Tim Hudak already indicating he would not back it, the decision of whether to keep the Wynne government alive fell into Horwath's hands.

"This budget is not a solid plan for the future," she said. "It's a mad dash to escape the scandals. It's time for change. We do not support this government any longer."

Will Wynne wait for budget vote?

With the Progressive Conservatives and NDP vowing to vote against the budget, the Liberal government appears poised to fall on what amounts to a confidence vote in the legislature.

Wynne could decide not to wait for the budget votes — there will actually be two — and could ask the lieutenant governor to dissolve the legislature and call an election.

Several large labour groups, including Unifor and the Ontario Federation of Labour, urged the NDP to pass the budget and avoid an election, but public-sector unions complained the fiscal plan puts jobs at risk.

Wynne said she will make an announcement later on Friday on whether the Liberals will drop the writ immediately, or whether the party will force a vote on the budget in the legislature.

"I'm disappointed that [Horwath] wouldn't have a meeting with me. I think there's a lot in this budget that needs to be implemented in this province," she told Belleville radio station CJBQ. "But I've said all along ... if we didn't have a partner in the legislature, then we would take this budget to the people of the province, and we will do that."

The NDP propped up the Liberals in the last two budgets, but negotiated major changes in each, including a tax on incomes over $500,000 and a 15 per cent average cut in auto insurance premiums.

Move a 'big gamble' for Horwath

CBC provincial affairs specialist Robert Fisher said the move to force an election is a "big gamble" for Horwath, particularly because the budget included so many spending measures designed to win NDP support.

"This was the best NDP budget a Liberal government could have delivered and yet it was not enough for Andrea Horwath," Fisher said Friday on CBC News Network.

Fisher said obviously Horwath was able to convince her caucus that forcing an election would improve the NDP's position in the legislature.

"If she doesn't, she might be looking for a new job the morning after the next election," said Fisher.

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